Use float rather than SkFixed for gradient TileProcs.

src/effects/gradients/SkClampRange.cpp

Index: src/effects/gradients/SkClampRange.cpp
diff --git a/src/effects/gradients/SkClampRange.cpp b/src/effects/gradients/SkClampRange.cpp
index 0bf30f14eafda9b480f13a8a5a23b8cd2210851f..5bf0c6dbe33f8f5b8fc11639519f012f72232d06 100644
--- a/src/effects/gradients/SkClampRange.cpp
+++ b/src/effects/gradients/SkClampRange.cpp
@@ -65,9 +65,12 @@ void SkClampRange::initFor1(SkGradFixed fx) {
     }
 }
 
-void SkClampRange::init(SkGradFixed fx0, SkGradFixed dx0, int count, int v0, int v1) {
+void SkClampRange::init(float float_fx0, float float_dx0, int count, int v0, int v1) {
     SkASSERT(count > 0);
 
+    SkGradFixed fx0 = SkFloatToGradFixed(float_fx0);
+    SkGradFixed dx0 = SkFloatToGradFixed(float_dx0);
+
     fV0 = v0;
     fV1 = v1;